Abstract

Riley’s (1994) Stuttering Severity Instrument version three (SSI-3) has three components: a symptom frequency measure (%SS), average duration of the three longest stutters and a physical concomitant (PC) score. An assessment of whether it was necessary to use all of these when using SSI-3 to identify which children are at risk of speech difficulty was performed. Participants were 879 reception class children aged 4-6 years from UK schools. The distributions of the separate components of SSI-3 were examined. Departures from normality were noted for each component. The features seen in the distribution of the individual components were also apparent in the distribution of overall scores (this was not normal and had multiple modes). These findings undermine the usefulness of the overall measure for identifying children at risk of speech difficulty. Prior work used a fixed SSI-3 threshold to identify at risk children. Classification of children as fluent or at risk based on this threshold was compared with classifications based on thresholds applied to the individual components. Classifications were comparable for %SS, but less satisfactory for duration and PC. These findings suggests that %SS performs similarly to overall SSI-3 scores when used to identify at risk children. Riley (1994) conducted correlation analyses to justify the inclusion of all components in SSI-3. This involved part (individual component) scores that were correlated with whole (overall SSI-3) scores. These results were replicated. However, correlations are spuriously inflated if this procedure is employed. Additional correlation analyses showed that part-‘whole’ correlations were low when the component used as the part was excluded from the ‘whole’. Thus Riley’s justification for using all components is questionable. Physical concomitants measured on five-point scales (as Riley specified) were no more sensitive than when the scale was collapsed to three or to two points. Since judgments were not affected when the scale was decimated, judges did not appear to be able to use the original scale. Procedures for identifying at risk children in schools need to be short and easy to administer. Thus, since there is no justification for including all components of SSI-3 and duration and physical concomitants are not sensitive measures of fluency, a procedure based on the frequency measure alone is appropriate for use in schools.

Type:

Article

Title:

Is it necessary to assess fluent symptoms, duration of dysfluent events and physical concomitants when identifying children who have speech difficulties?

This is an Accepted Manuscript of an article published by Taylor & Francis in Clinical Linguistics and Phonetics on 17 June 2016, available online: http://www.tandfonline.com/doi/full/10.1080/02699206.2016.1179345